Add changelog README and update roadmap with reference projects

- Created a new README file for the changelog to outline version history.
- Updated the roadmap documentation to replace the contribution section with a list of reference projects, enhancing resource visibility.

docs/overrides/partials/header.html

@@ -0,0 +1,118 @@
+<!--
+  Copyright (c) 2016-2025 Martin Donath <martin.donath@squidfunk.com>
+
+  Permission is hereby granted, free of charge, to any person obtaining a copy
+  of this software and associated documentation files (the "Software"), to
+  deal in the Software without restriction, including without limitation the
+  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+  sell copies of the Software, and to permit persons to whom the Software is
+  furnished to do so, subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be included in
+  all copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+  IN THE SOFTWARE.
+-->
+
+<!-- Determine classes -->
+{% set class = "md-header" %}
+{% if "navigation.tabs.sticky" in features %}
+  {% set class = class ~ " md-header--shadow md-header--lifted" %}
+{% elif "navigation.tabs" not in features %}
+  {% set class = class ~ " md-header--shadow" %}
+{% endif %}
+
+<!-- Header -->
+<header class="{{ class }}" data-md-component="header">
+  <nav
+    class="md-header__inner md-grid"
+    aria-label="{{ lang.t('header') }}"
+  >
+
+    <!-- Link to home -->
+    <a
+      href="{{ config.extra.homepage | d(nav.homepage.url, true) | url }}"
+      title="{{ config.site_name | e }}"
+      class="md-header__button md-logo"
+      aria-label="{{ config.site_name }}"
+      data-md-component="logo"
+    >
+      {% include "partials/logo.html" %}
+    </a>
+
+    <!-- Button to open drawer -->
+    <label class="md-header__button md-icon" for="__drawer">
+      {% set icon = config.theme.icon.menu or "material/menu" %}
+      {% include ".icons/" ~ icon ~ ".svg" %}
+    </label>
+
+    <!-- Header title (data-md-component removed so title stays site_name on scroll) -->
+    <div class="md-header__title">
+      <div class="md-header__ellipsis">
+        <div class="md-header__topic">
+          <span class="md-ellipsis">
+            {{ config.site_name }}
+          </span>
+        </div>
+        <div class="md-header__topic" data-md-component="header-topic">
+          <span class="md-ellipsis">
+            {{ config.site_name }}
+          </span>
+        </div>
+      </div>
+    </div>
+
+    <!-- Color palette toggle -->
+    {% if config.theme.palette %}
+      {% if not config.theme.palette is mapping %}
+        {% include "partials/palette.html" %}
+      {% endif %}
+    {% endif %}
+
+    <!-- User preference: color palette -->
+    {% if not config.theme.palette is mapping %}
+      {% include "partials/javascripts/palette.html" %}
+    {% endif %}
+
+    <!-- Site language selector -->
+    {% if config.extra.alternate %}
+      {% include "partials/alternate.html" %}
+    {% endif %}
+
+    <!-- Button to open search modal -->
+    {% if "material/search" in config.plugins %}
+      {% set search = config.plugins["material/search"] | attr("config") %}
+
+      <!-- Check if search is actually enabled - see https://t.ly/DT_0V -->
+      {% if search.enabled %}
+        <label class="md-header__button md-icon" for="__search">
+          {% set icon = config.theme.icon.search or "material/magnify" %}
+          {% include ".icons/" ~ icon ~ ".svg" %}
+        </label>
+
+        <!-- Search interface -->
+        {% include "partials/search.html" %}
+      {% endif %}
+    {% endif %}
+
+    <!-- Repository information -->
+    {% if config.repo_url %}
+      <div class="md-header__source">
+        {% include "partials/source.html" %}
+      </div>
+    {% endif %}
+  </nav>
+
+  <!-- Navigation tabs (sticky) -->
+  {% if "navigation.tabs.sticky" in features %}
+    {% if "navigation.tabs" in features %}
+      {% include "partials/tabs.html" %}
+    {% endif %}
+  {% endif %}
+</header>